Chinese medical sciences journal = Chung-kuo i hsueh k'o hsueh tsa chih最新文献

Objective: To investigate the alterations of cardiac electrophysiological properties and substantial mechanism and find the stable arrhythmia mouse model in Kunming (KM) and C57BL6/J (C57) mice.

Methods: Electrocardiogram recordings were used to analyze the QT interval in vivo, and mono- phasic action potential of right and left ventricular epicardium was recorded to elicit changes of action potential duration (APD) in conventional and programmed electrical stimulation (PES). Transient outward potassium current (Ito) was recorded via whole-cell patch-clamp technique in single right and left epicardial myocytes.

Results: QT interval was prolonged in KM mice relative to C57 mice (62.51±4.47 ms vs. 52.59±4.85 ms, P<0.05) The APD at 50% repolarization of the left ventricular epicardium (18.60±0.91 ms vs. 12.90±0.35 ms), and APDs at 50% (17.31±6.05 ms vs. 12.00±3.24 ms) and 70% repolarization (36.13±5.32 ms vs. 21.95±8.06 ms) of the right ventricular epicardium in KM mice were more sensitive to PES-induced ventricular tachycardia (25%, 3 of 12 hearts), and especially to Burst-induced ventricular tachycardia (50%, 6 of 12 hearts)compared with C57 mice, which were 20% (2 of 10 hearts) and 30% (3 of 10 hearts) respectively. Ito densities both in the left and right ventricular epicardial myocytes from KM mice were significantly decreased compared with C57 mice, respectively (all P<0.01).

Conclusion: Our data showed that KM mice with the prolonged QT interval and APD are vulnerabilities to ventricular arrhythmia, which are attributed to lower Ito densities in ventricular myocytes obtained from KM mice than that from C57 mice.

Objective: To determine the safety and efficacy of fresh frozen plasma (FFP) infusion for the treatment of hereditary angioedema (HAE).

Methods: The medical records of patients with HAE admitted to Peking Union Medical College Hospital who had received FFP infusion during 2004 and 2010 were reviewed and PubMed database from 1966 to the present were searched using the following hereditary angioedema and fresh frozen plasma. The patient's age, sex, body location of HAE attacks, the dose of FFP infusion, time of beginning to improvement, time to complete remission, complication, C1 inhibitor activity, and outcome were analyzed.

Results: A total of 13 enrolled patients (7 male and 6 female) received 16 times of FFP infusion, including 2 patients undergoing FFP infusion in Peking Union Medical College Hospital and 11 patients reported in the literature. The mean dosage of FFP infusion was 586∓337 mL. Two cases suffered from worsening abdominal pain and one case experienced skin rash. Only 1 patient had no improvement in symptom owing to transfusion related reaction. There was a definite improvement in symptom 49∓19 minutes after beginning FFP infusion. The remission time decreased from 61.7∓27.0 hours to 3.3 (2.0, 12.0) hours after FFP infusion. FFP infusion was effective for both type I and type II HAE.

Conclusion: FFP seems to be safe and effective for acute attacks of HAE.

Objective: To investigate the main proteinases responsible for CD16b shedding under different stimulators.

Methods: HEK293 cell line stably expressing CD16b was constructed by lentivirus system. The cell line was then overexpressed with a disintegrin and metalloproteinase 10 (ADAM10) or ADAM17, suppressed with short hairpin RNA of ADAM10 or ADAM17, and reconstituted with ADAM10 or ADAM17, respectively. After each treatment, the cell line was stimulated with ionomycin or phorbol 12-myristate- 13-acetate (PMA) for 12 hours. The soluble CD16b released from cell membrane was detected by immunoprecipition and immunoblot. Quantitation was then implemented to compare the amount of soluble CD16b in cell supernatant after stimulation.

Results: HEK293 cell line stably expressing CD16b was successfully established. When CD16b expressing cell line was overexpressed with ADAM10, shedding of CD16b was increased after stimulation with ionomycin but not PMA; when the cell line overexpressed with ADAM17, shedding of CD16b was increased after stimulation with PMA but not ionomycin. Similarly, when ADAM10 was suppressed by short hairpin RNA, CD16b shedding was decreased after stimulation with ionomycin; when ADAM17 was suppressed by short hairpin RNA, CD16b shedding was decreased after stimulation with PMA. The shedding of CD16b was increased again when CD16b expressing cell line was reconstituted with ADAM10 and stimulated by ionomycin or reconstituted with ADAM17 and stimulated by PMA.

Conclusions: Both ADAM10 and ADAM17 could shed CD16b, but they possess differed preferences. ADAM10 is the main sheddase under stimulation of ionomycin, while ADAM17 is the main sheddase under stimulation of PMA.

Objective: To explore the correlations between serum uric acid (UA) levels and the clinical and cerebrospinal fluid (CSF) parameters of multiple sclerosis (MS).

Methods: The medical reports of 47 MS patients admitted to Peking Union Medical College Hospital during 2008 and 2010 were reviewed. And 49 age- and gender-matched cerebral infarction patients were enrolled as control. The mean serum UA level of the MS patients was compared with that of the control group. The correlations between the UA levels and the clinical parameters including gender, disease duration, relapse rate, and disease disabilities as assessed by the Expanded Disability Status Scale score, were explored. Forty-one patients had CSF examinations. The correlations between the UA levels and the CSF parameters reflecting inflammation and tissue damage, including CSF protein, white blood cell count, oligoclonal band, 24-hour IgG index, and myelin basic protein, were also investigated.

Results: The mean serum UA level in the MS patients was lower than that in the control group (247.75±52.59 µmol/L vs. 277.94±74.33 µmol/L, P=0.025) and inversely correlated with the relapse rate (P=0.049). MS patients with lower serum UA levels tended to have higher white blood cell counts and myelin basic protein level. But there was no correlation between CSF protein levels (r=0.165, P=0.273), white blood cell counts (r=-0.051, P=0.732), IgG index (r=0. 045, P=0.802), or myelin basic protein level (r=-0.248, P=0.145) and the serum UA level, respectively.

Conclusion: In MS patients, UA levels might partly reflect the extent of disability and inflammation.

Objective: To evaluate the safety and efficiency of hemi-semi laminectomy approach for the microsurgical treatment of spinal schwannomas.

Methods: A total of 22 patients underwent hemi-semi laminectomy for the microsurgical removal of spinal schwannomas during a period of 2009 and 2011 in Affiliated Hospital of Nantong University. We retrospectively analyzed the clinical outcomes of these patients.

Results: Of them, 5 cases were diagnosed with cervical schwannomas, 9 with thoracic schwannomas, and 8 with lumbar schwannomas. All the tumors including two dumbbell schwannomas were totally removed without major complications. Postoperatively, all patients were followed up from 6 to 36 months. The symptoms and signs were obviously improved, and no tumor recurrence or spinal deformity occurred.

Conclusion: Hemi-semi laminectomy is a safe and effective method for resection of spinal schwannomas.